Process of and apparatus for treating artificial threads



Aug. 28, 1934. H c STUHLMANN AL 1,971,627

PROCESS OF AND APPARATUS FOR TREATING ARTIFICIAL THREADS Filed May 8, 1929 Patented Aug. 28, 1934 UNITED STATES PROCESS OF AND APPARATUS FDR. TREAT- IN G ARTIFICIAL THREADS Hans Caesar Stuhlmann and Otto Weitermann,

Premnitz, Germany, assignors to I. G. Farbenindustrie Aktiengesellschaft,

Frankfort-on the-Main, Germany, a corporation of Germany Application May 8, 1929, Serial No. 361,490

Germany May 11. 1928 3 Claims.

Our present invention relates to a process and apparatus for washing and after-treating practically endless, thick bundles of freshly coagulated artificial threads of high total titer and for feed- 5 ing them after washing, subsequently treating and drying in a finished form to a receiving apparatus.

Other objects of our invention will be seen from the detailed specification following hereafter.

The invention is based on the observation that 1 it is possible to free freshly spun bundles of threads from the adhering constituents of the precipitating bath; also to subject them to further treatment, to washing, to bleaching and to soaping in such a very short time, that the operation of washing and. the subsequent treatment may be performed in an uninterrupted mannerduring the passage of the fiber bundles from the spinning bath to the receiving device, this passage even beinga straight line.

It has been found that two conditions mus be fulfilled:

1: It is necessary to conduct the bundle under such a low tension through the baths that the resistance of the liquids of the baths causes the single fibers to disperse, so that the bundle be= comes spread out.

2: It is necessary to free the bundle leaving the baths from the adhering liquid before it enters a further bath.

The process consists, therefore, in conducting the freshly spun bundles of threads of high total titer through successively arranged baths for washing and other treatment, between which pressure rollers of rubber are arranged, which are so driven that the speed of the draft which they produce can be varied.

By regulating the draught of each pair of squeezing rollers, the fiber bundle is caused to pass through each bath at such a speed that it is placed under no tension, or only under a very low tension. Moreover, the liquids adhering to the fiber bundles,- are removed by the squeezing rollers, so that no bath can be diluted or contaminated by liquid or the preceding bath adhering to the bundle.

For example, in the viscose process freshly spun bundles of fibers extruded from 120 spinning nozzles, each with 600 perforations of 0.10 mm diameter, are brought together after leaving the coagulating bath so that with a speed of draft of 50-60 metres a bundle of fibers of a total titer of about 60,00080,000 denier-s is produced. Advantageously the treating devices are so placed with reference to the spinning devices that large differences in the length of the path are avoided.

The collected bundles of threads are guided between squeezing rollers, or even in a single-operation, around a reel through a trough of 5 meter length filled with water of a temperature of about 60-80" C. if necessary, this washing is repeated; then the bundle which is now free from acid is again led between another pair of squeezing rollers and then. passes through a desulfurizing bath,

a water bath, an acid bath, a water bath, a soap bath and so on.

As mentioned above, between each pair of baths, the bandpasses between a pair of squeezing rollers, the speed of which can be regulated. In each bath the bundle of threads is held continuously under the surface of the liquid by guiding de-- vices which may be of glass.

If no, or only slight tension, is applied to the bundle in passage through the treating baths, or some of them by a corresponding regulation of the speed of each pair of squeezing rollers, the bundle hangs slightly, so that the liquid can easily come into contact with the individual fibers. Thus, with a speed of 60 meters per minute, a so given point of the bundle requires only 5 to 10 seconds for its passage through the bath; this short period of immersion in the different baths is sufi'icient for the completion of the after-treatment.

A particular surprising advantage of the invention resides in the fact, that in addition to mechanical treatment with liquids a chemical treating as a de-sulfurizing operation of the bundles of threads also is possible.

After leaving the final bath, the after-treated fiber bundle is once more subjected to squeezing and may now, after passage through the drying apparatus, be wound up as an endless band or passed through a cutting machine for producing staple fiber.

An example of an arrangement in. accordance with the invention is shown in the accompanying diagrammatic drawing, in which Fig. 1 is a plan and Fig. 2 and elevation.

a represents the bundle of threads, I) a pair of squeezing rollers the speed of which can be regulated by any suitable means not shown, 0 a trough or the like for receiving the bath liquid. d are guiding devices.

What we claim:'

1. An apparatus for washing and subsequently chemically treating freshly produced bundles of artificial fibers of a total titer of the order of at least 60,000 deniers on their way between the coagulation bath and the collecting device, which apparatus comprises a number of troughs, and a pair ofsqueezing rollers between each pair of adjacent troughs, before the first trough and behind the last trough, each pair of rollers being independently driven and independently controllable as to speed of rotation, whereby the bundle being treated may be moved through the respective troughs under no tension. 1

2. A process for washing and subsequently chemically treating freshly produced bundles of artificial fibers of a, total titer of the order of at least 60,000 to 80,000deniers on their way between the coagulation bath and the collecting deder no tension and subjecting the bundle to squeezing between the different treating baths.

3. A process for washing and subsequently chemically treating freshly produced bundles of artificial fibers of a total titer ofthe order of at least 60,000 to 80,000 deniers on their way be? tween the coagulation bath and the collecting device, which comprises opening up the bundle of fibers as the same is conducted in uninterrupted operation through the baths for treatment with a speed allowing a given point of the bundle to remain for about 5 to 10 seconds in the single baths by moving the bundle through the baths while under no tension, and subjecting the bundle to squeezing between the diflerent treating baths.

HANS CAESAR STUHIMANN. QTI'O W'EITERMANN. 

